$30m plan for Mangawhai sewerage gets go-ahead

The Kaipara District Council has accepted a proposal for the Australian company Earth Tech to design, build, finance and operate a Mangawhai sewerage scheme expected to cost $29.8 million.
The agreement, signed before the council meeting at Dargaville on Wednesday, marked a big milestone in the Mangawhai Ecocare project which was launched in the early 1990s to deal with harbour pollution.
Another Australian firm, Simon Engineering, was close to getting the green light for a $17.5 million Ecocare sewerage construction scheme late last year with but the company went under financially.
The silver lining on this setback was that the council lost no money over it and was able to pursue negotiations with other tenderers for the project, with Earth Tech emerging as the preferred contractor.
No start date has been set down for construction.
The proposed sewerage scheme will initially service 2000 sections and will have the capacity to hook up about 50 new sections annually for 25 years to eventually service 3250 sections.
The council has considered four funding options for the project and on Wednesday it indicated with a vote that its preferred option was to fund capital costs with a combination of a uniform targeted rate, development contributions and pan charges. Operating costs would be covered by a uniform annual charge.
The uniform targeted rates being considered are a $5203 one-off connection fee or payments of $337.50 annually for 25 years for sections created before July 1 next year. A one-off development contribution of $9797 could be levied on sections created after July 1. A uniform annual charge of $630 could be imposed on each pan.
Ecocare has been awarded a provisional contribution of $6.63 million from the Government's sanitary works subsidy scheme and the council also voted to channel unused subsidy cash into reducing the capital or connection costs for the owners of sections created before March 21, 2003.
The Ecocare project does not include connecting houses to the reticulation network at property boundaries. This will be the responsibility of the property owners, expected to hire registered plumbers.
All sections that have the reticulation network available will pay a one-off targeted rate. If they have no dwelling to be hooked up the owners will be charged 50 percent of the uniform annual charge.
The wastewater plant in Mangawhai Park will be fenced and screened with trees and bushes to reduce its visual impact.
Effluent will be disposed of to land, with the exact location still to be determined. Possible reuse options will be considered to minimise the amount of discharge required.
Sections in the Mangawhai Village will largely be serviced by a vacuum sewage collection system to reduce the size of the pumps and pipes required.
Mangawhai Heads will largely be serviced by a modified conventional gravity collection system where practicable. About 130 sections will have a low-pressure services system comprising a self-contained polyethylene tank with a grinder pump that will pump effluent to the gravity collection system via a small bore pressure pipeline.
* Start date depends on:
• Obtaining resource consents for an effluent disposal site when one is found, and consents will also be needed for pump stations and a treatment facility to be built in Mangawhai Park. Completing council consultation with the community. A final statement of proposal will be released in March next year, with public meetings at Maungaturoto on March 29, Mangawhai on March 31 and Dargaville on April 3. Submissions close on April 21, hearings are scheduled for May 8-10 and a final decision to proceed with construction is expected on June 7.
• The proposed Ecocare sewerage scheme is expected to end harbour pollution at Mangawhai, which has a population of 1400 swelling to 4500 over summer with a peak of about 6500, including daily visitors. The harbour and groundwater has been degraded since at least 1976 when surveys indicated unacceptable levels of human waste and other pollution.